Brake shoe



Jan. 2, 1934. w W N g 1,941,646

BRAKE SHOE Filed Feb. 20, 1935 2 Sheets-Sheet l war i 4 ATTORN EY Jan. 2, 1934,

w. H. WINTERS 1,941,646

BRAKE SHOE 7 Filed Feb. 20, 1933 2 Sheets-Sheet 2 mill-Q ll/A ATTORN EY Patented Jan. 2, 1934 PATENT OFFICE BRAKE SHOE Wilbur H. Winters, Larchmont, N. 'Y., assignor to The American Brake Shoe and Foundry Company, Wilmington, Del., a corporation of Delaware I Application February 20, 1933. Serial No. 657,554

7 Claims.

This invention relates to brake shoes of the'type which are provided with aback curved toconform with the curvature of the shoe and embedded in the body thereof. It has been customary to make '8 the back out of a continuous flat strip of steel recessed at its side edges midway between its ends to accommodate the attaching lug strap and provided with elongated openings at each side of the recessed central portion or otherwise made to receive the'body metal during the casting operation for anchoring the back to the body. This type of back is commonly referred to as a plate back. 1

The object of the invention is to reenforce and strengthen the back of a brake shoe in a simple and effective manner to resist the vibration and other strains and stresses to which the back is subjected when the bodyof the shoe fractures so that it will; continue to hold the parts of the body together until'the predetermined limit of-wear of the shoehas been reached.

A more particularobject of the invention is to increase the strength and. rigidity of the back by securing a reenforce to the inner concave side thereof to provide a truss at the central portion oftheback. U v

g In the accompanying drawings illustrating se-' lected embodiments .of the invention,

Fig. 1 is a sideview of a shoe partly in section showing a reenforced back of my invention embedded therein.

Fig. 2 is a plan view of apart of the reenforced back shown in Fig. 1 with thebody of the shoe shown in broken lines. 7

Fig. 3 is a sectionalview on the line 33 of Fig-L 1 1 Fig. 4 is a plan view of a part of a reenforced back showing another form of the reenforce.

Fig.5is a side edgeviewrof a part of the reenforced back which is shown in Fig. 4.

, Fig.6 is asectional view on .the line 6-6 of Fig. 5. r

Fig. 7 is a sectional view on the line 7-7 of Fig. 5.

Fig. 8 is a View similar to Fig. 4 showing another form of reenforce.

Fig. 9 is a side edge-view of apart of the reenforced back shown in Fig. 8.

Fig. 10 is a sectional view on the line 10-10 of Fig. 9.

Fig. 11 is a view similar to Fig. 4 showing another form of reenforce.

Fig. 12 is a side edge view of a part of the reenforced back shown in Fig. 11.

Fig. 13 is a view similar to Fig. 4 showing another form of reenforce.

Fig. 14 is a side edge view of a part of the reenforced back shown in Fig. 13.

Fig. 15 is a sectional view on the line 1515 of Fig. 14.

Fig. 16 is a view similar to Fig. 4 showing another form of reenforce.

Fig. 17 is a side edge View showing a part of the reenforced. back shown in Fig. 16.

Fig. 18 is a sectional view on the line 18-18 of Fig. 17.

Fig. 19 is a view similar to Fig. 4 showing another form of reenforce.

Fig. 20 is a side edge View of a part of the reenforced back shown in Fig. 19.

Fig. 21 is a sectional view on the line 21-21 of Fig. 20.

Fig. 22 is a view similar to Fig. 4 showing another form of reenforce.

Fig. 23 is a side edge View of a part of the reenforced back shown in Fig. 22.

Fig. 24 is a sectional View on the line 24-24 of Fig. 23.

Fig. 25 is a view similar to Fig. 4 showing another form of reenforce.

Fig. 26 is a side edge view of a part of the reenforced back shown in Fig. 25.

Fig. 27 is a sectional view on the line 27-27 of Fig. 26. 1

Referring to Figs. l-3, 1 is the body of a brake shoe having a plate back 2 embedded therein and provided with an end lug 3, guide lugs 4 and an attaching lug 5. The attaching lug includes a lug strap 6 which engages recesses 7 in the side edges of the plate back and has its ends 8 bent under the back. Plate backs have been made in a variety of forms heretofore and for the purposes of this invention I have chosen a simple form which is also, I believe, the best known form and is provided with a slot 9 in each end portion and beveled side edges 10 to make anchoring engagement with the body metal.

The plate back is curved in an arc corresponding to the body of the shoe which is made to fit the wheel and my invention provides a reenforce for the back in the form of a strut or chord 11 which extends across the metal portion of the back and is secured rigidly at its ends to the back. The reenforce provides a truss for the back which adds greatly to its strength and will prevent the back from breaking under ordinary service conditions, after the body of the shoe has fractured, so that the shoe may continue in use until it has reached its predetermined limit of wear. The ends of the reenforce are rigidly secured to the inner side of the back, and for this purpose they are preferably bent slightly as shown at 12 to conform generally with the curvature of the back and are welded at 13 to the back. Each end portion of the reenforce preferably has a slot 14 conforming generally with the slot 9 in the back, and the reenforce may also be recessed at its side edges to conform with the recesses 7 in the back but I prefer not to recess the reenforce, and I have not shown it recessed, because the body metal may flow around the side edges of the reenforce and through the recesses '7 to form the attaching lug.

In Figs. 4-7, the reenforce 15 is in the form of a strip curved transversely with its end portions provided with openings 16, instead of being slotted, and its end corners 1'7 are bent to conform with the back to which they are welded.

In Figs. 8-10, the reenforce 18 has its side edges 19 bent inward and the side and end edges have dovetail recesses 20.

In Figs. 11 and 12, the reenforce 21 has its ends 22 bent away from the back 2 and welded at 23 to the back.

In Figs. 13-15, the reenforce 24 has its side edges 25 bent away from the back 2 and its ends welded to the back.

In Figs. 16-18, the reenforce 26 is curved transversely with its side edges 2'7 directed away from the back.

In Figs. 19-21, the reenforce has a central 1ongitudinal channel 28 which engages the back 2, and laterally extending marginal side edges 29 which are spaced from the back.

In Figs. 22-24, the reenforce 30 is curved to correspond substantially with the curvature of the back 2 and the marginal edges of the reenforce intermediate of its end portions are bent away from the back and toward each other so that at the middle of the reenforce they are in substantial opposition as shown in the sectional view, Fig. 24.

In Figs. 25-27, the reenforce 32 is curved like the reenforce 30 and its marginal side edges 33 are bent away from the back between the ends of the reenforce so that at the middle of the reenforce they are in substantial parallelism as shown in the sectional view, Fig. 27.

In all the several forms of the invention hereinbefore described, the reenforce is rigidly secured to the back by some form of welding. The reenforces shown are slotted at the ends or provided with openings to register with the slots in the back so that the body metal may flow therethrough into the space between the reenforce and the back. The body metal will, of course, flow into this space between the reenforce and the back at the side edges of the reenforce and back.

The reenforce provides a truss at the central portion of the back and adds greatly to the strength and rigidity of the shoe and the back and when the body of the shoe becomes fractured and the back is subjected to vibration and other strains of service the reenforce will provide the strength and rigidity required of the back to enable it to hold the fractured parts of the body together compactly until the shoe has worn out in service. It is found in practice that the body of a brake shoe is liable to break transversely on either side of and near to the attaching lug, and the reenforce is of a length to bridge and provide a truss at that part of the shoe where the principal breakage of the body occurs. The reenforce not only adds to the strength and rigidity of the back to enable it to withstand the vibration and other strains of service, but it also provides an additional anchorage for the body which assists in holding the parts together.

The invention is capable of use in a variety of forms and with different kinds of backs and in different kinds of shoes and I reserve the right to make any changes that may be necessary or desirable for difierent adaptations within the scope of the following claims:

I claim:

1. A brake shoe comprising a body, a back embedded in the body, said back being bent longitudinally in an arc, and a reenforce secured at its ends to the inner concave side of the back and providing a truss at the central portion of the back. 7

2. A brake shoe comprising a body, a back emembedded in the body, said back being bent longitudinally in an arc, and a reenforce secured to the back and extending across the inner concave side of the back as a chord of the arc of curvature of the back.

3. A brake shoe comprising a body, a back embedded in the body, said back being bent longitudinally in an arc, and a reenforce having its ends secured to the back and extending across the inner concave side of the back as a chord of the arc of curvature of the back.

4. A brake shoe comprising a body, a back embedded in the body, said back being bent 1ongitudinally in an arc, and a reenforce secured at its ends to the inner concave side of the back and providing a truss at the central portion of the back, said back being bent transversely.

5. A brake shoe comprising a. body, a back embedded in the body, said back being bent longitudinally in an arc, and a reenforce secured at its ends to the inner concave side of the back and providing a truss at the central portion of the back, the ends of the reenforce being bent to lie substantially parallel with the inner side of the back.

6. A brake shoe comprising a body, a back embedded in the body, said back being bent longitudinally in an arc, and a reenforce secured at its ends to the inner concave side of the back and providing a truss at the central portion of the back, the space between the back and the reenforce being filled withbody metal.

7. A brake shoe comprising a body,-a back embedded in the body, said back being bent longitudinally in an arc, and a reenforce securedat its ends to the inner concave side of the back and providing a trussat'the central portion of the back, said back and said reenforce having openings in their end portions to permit the flowof body metal therein during the casting operation,

. VVILBUR H. WINTERS.- 

